1. Field of the Invention
The present invention generally relates to the detection of a character region in an image, and more particularly, to a character region extracting apparatus and method based on character stroke width calculation.
2. Description of the Related Art
Generally, a character extraction method recognizes a character included in an image, and extracts the recognized character region.
Characters existing in such an image provide various information items for the image. Therefore, research is being conducted in the area of applications and services for recognizing characters in an image and providing information related to the characters. For this purpose, it is first necessary is to detect a character-positioned region in such an image.
A character region is detected on the basis of edge, color and contrast characteristics, and it is confirmed whether the detected region actually contains one or more characters. For this purpose, character stroke widths are calculated, and the detected region is finally determined as a character region if the character stroke widths are constant. Considering the fact that character stroke widths are constant except for some fonts and sign boards, to which complicated designs are applied, the character stroke widths are used for detecting a character region.
As described above, in the past, character edge, color and contrast characteristics were used so as to detect a character region, in which case character stroke widths were calculated mainly along a scan line in an image region.
However, there was a problem in that a limitation exists in calculating correct character stroke widths since stroke widths may be erroneously calculated as the scan line passes positions of the characters or the characters themselves are inclined and, hence, the scan line does not pass one or more character strokes perpendicularly.